Аннотация:Regulation of retrotransposon activity in somatic tissues is a complex mechanism that has still notbeen studied in detail. It is strongly believed that siRNA interference is main mechanism of retrotransposonactivity regulation outside the gonads, but recently was demonstrated that piRNA interference participates inretrotransposon repression during somatic tissue development. In this work, using RT-PCR, we demonstrated that during ontogenesis piRNA interference determinates retrotransposon expression level on imagostage and retrotransposons demonstrate tissue-specific expression. The major factor of retrotransposon tissue-specific expression is presence of transcription factor binding sites in their regulatory regions.